From 18bd1963aef94e0186ad435f8a497b74c00b73de Mon Sep 17 00:00:00 2001 From: Jerry Hoemann Date: Mon, 20 Aug 2018 13:31:23 -0600 Subject: watchdog: hpwdt: Update Driver Documentation. Remove references to deprecated features like NMI sourcing and obsoleted module parameters. Add details concerning new module parameter pretimeout and tips to programming it. Signed-off-by: Jerry Hoemann Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- Documentation/watchdog/hpwdt.txt | 93 ++++++++++++++-------------------------- 1 file changed, 31 insertions(+), 62 deletions(-) (limited to 'Documentation') diff --git a/Documentation/watchdog/hpwdt.txt b/Documentation/watchdog/hpwdt.txt index 6d866c537127..55df692c5595 100644 --- a/Documentation/watchdog/hpwdt.txt +++ b/Documentation/watchdog/hpwdt.txt @@ -1,15 +1,12 @@ -Last reviewed: 05/20/2016 +Last reviewed: 08/20/2018 HPE iLO NMI Watchdog Driver - NMI sourcing for iLO based ProLiant Servers - Documentation and Driver by - Thomas Mingarelli + for iLO based ProLiant Servers The HPE iLO NMI Watchdog driver is a kernel module that provides basic - watchdog functionality and the added benefit of NMI sourcing. Both the - watchdog functionality and the NMI sourcing capability need to be enabled - by the user. Remember that the two modes are not dependent on one another. - A user can have the NMI sourcing without the watchdog timer and vice-versa. + watchdog functionality and handler for the iLO "Generate NMI to System" + virtual button. + All references to iLO in this document imply it also works on iLO2 and all subsequent generations. @@ -21,12 +18,16 @@ Last reviewed: 05/20/2016 not be updated in a timely fashion and a hardware system reset (also known as an Automatic Server Recovery (ASR)) event will occur. - The hpwdt driver also has three (3) module parameters. They are the following: + The hpwdt driver also has the following module parameters: soft_margin - allows the user to set the watchdog timer value. Default value is 30 seconds. - allow_kdump - allows the user to save off a kernel dump image after an NMI. - Default value is 1/ON + timeout - an alias of soft_margin. + pretimeout - allows the user to set the watchdog pretimeout value. + This is the number of seconds before timeout when an + NMI is delivered to the system. Setting the value to + zero disables the pretimeout NMI. + Default value is 9 seconds. nowayout - basic watchdog parameter that does not allow the timer to be restarted or an impending ASR to be escaped. Default value is set when compiling the kernel. If it is set @@ -37,61 +38,29 @@ Last reviewed: 05/20/2016 interface to /dev/watchdog can be found in Documentation/watchdog/watchdog-api.txt and Documentation/IPMI.txt. - The NMI sourcing capability is disabled by default due to the inability to - distinguish between "NMI Watchdog Ticks" and "HW generated NMI events" in the - Linux kernel. What this means is that the hpwdt nmi handler code is called - each time the NMI signal fires off. This could amount to several thousands of - NMIs in a matter of seconds. If a user sees the Linux kernel's "dazed and - confused" message in the logs or if the system gets into a hung state, then - the hpwdt driver can be reloaded. - - 1. If the kernel has not been booted with nmi_watchdog turned off then - edit and place the nmi_watchdog=0 at the end of the currently booting - kernel line. Depending on your Linux distribution and platform setup: - For non-UEFI systems - /boot/grub/grub.conf or - /boot/grub/menu.lst - For UEFI systems - /boot/efi/EFI/distroname/grub.conf or - /boot/efi/efi/distroname/elilo.conf - 2. reboot the sever - 3. Once the system comes up perform a modprobe -r hpwdt - 4. modprobe /lib/modules/`uname -r`/kernel/drivers/watchdog/hpwdt.ko - - Now, the hpwdt can successfully receive and source the NMI and provide a log - message that details the reason for the NMI (as determined by the HPE BIOS). - - Below is a list of NMIs the HPE BIOS understands along with the associated - code (reason): - - No source found 00h - - Uncorrectable Memory Error 01h - - ASR NMI 1Bh - - PCI Parity Error 20h - - NMI Button Press 27h - - SB_BUS_NMI 28h - - ILO Doorbell NMI 29h - - ILO IOP NMI 2Ah - - ILO Watchdog NMI 2Bh - - Proc Throt NMI 2Ch + Due to limitations in the iLO hardware, the NMI pretimeout if enabled, + can only be set to 9 seconds. Attempts to set pretimeout to other + non-zero values will be rounded, possibly to zero. Users should verify + the pretimeout value after attempting to set pretimeout or timeout. - Front Side Bus NMI 2Dh + Upon receipt of an NMI from the iLO, the hpwdt driver will initiate a + panic. This is to allow for a crash dump to be collected. It is incumbent + upon the user to have properly configured the system for kdump. - PCI Express Error 2Fh + The default Linux kernel behavior upon panic is to print a kernel tombstone + and loop forever. This is generally not what a watchdog user wants. - DMA controller NMI 30h + For those wishing to learn more please see: + Documentation/kdump/kdump.txt + Documentation/admin-guide/kernel-parameters.txt (panic=) + Your Linux Distribution specific documentation. - Hypertransport/CSI Error 31h + If the hpwdt does not receive the NMI associated with an expiring timer, + the iLO will proceed to reset the system at timeout if the timer hasn't + been updated. +-- + The HPE iLO NMI Watchdog Driver and documentation were originally developed + by Tom Mingarelli. - -- Tom Mingarelli -- cgit v1.2.3 From d72e8256c20971b12cddd71d87c32284de7108fa Mon Sep 17 00:00:00 2001 From: Chris Brandt Date: Mon, 24 Sep 2018 08:58:16 -0500 Subject: dt-bindings: watchdog: renesas-wdt: Add support for R7S9210 Document support for RZ/A2 Signed-off-by: Chris Brandt Reviewed-by: Simon Horman Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- Documentation/devicetree/bindings/watchdog/renesas-wdt.txt | 1 + 1 file changed, 1 insertion(+) (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt b/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt index 9407212a85a8..a9e49da6fa24 100644 --- a/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt +++ b/Documentation/devicetree/bindings/watchdog/renesas-wdt.txt @@ -20,6 +20,7 @@ Required properties: - "renesas,r8a77990-wdt" (R-Car E3) - "renesas,r8a77995-wdt" (R-Car D3) - "renesas,r7s72100-wdt" (RZ/A1) + - "renesas,r7s9210-wdt" (RZ/A2) The generic compatible string must be: - "renesas,rza-wdt" for RZ/A - "renesas,rcar-gen2-wdt" for R-Car Gen2 and RZ/G1 -- cgit v1.2.3 From 270c4265f259e4f9695b86b1ded00f7f202ecba4 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Mon, 17 Sep 2018 06:22:53 +0000 Subject: dt-bindings: watchdog: add mpc8xxx-wdt support Add description of DT bindings for mpc8xxx-wdt driver which handles the CPU watchdog timer on the mpc83xx, mpc86xx and mpc8xx. Signed-off-by: Christophe Leroy Reviewed-by: Rob Herring Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- .../devicetree/bindings/watchdog/mpc8xxx-wdt.txt | 25 ++++++++++++++++++++++ 1 file changed, 25 insertions(+) create mode 100644 Documentation/devicetree/bindings/watchdog/mpc8xxx-wdt.txt (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/watchdog/mpc8xxx-wdt.txt b/Documentation/devicetree/bindings/watchdog/mpc8xxx-wdt.txt new file mode 100644 index 000000000000..a384ff5b3ce8 --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/mpc8xxx-wdt.txt @@ -0,0 +1,25 @@ +* Freescale mpc8xxx watchdog driver (For 83xx, 86xx and 8xx) + +Required properties: +- compatible: Shall contain one of the following: + "mpc83xx_wdt" for an mpc83xx + "fsl,mpc8610-wdt" for an mpc86xx + "fsl,mpc823-wdt" for an mpc8xx +- reg: base physical address and length of the area hosting the + watchdog registers. + On the 83xx, "Watchdog Timer Registers" area: <0x200 0x100> + On the 86xx, "Watchdog Timer Registers" area: <0xe4000 0x100> + On the 8xx, "General System Interface Unit" area: <0x0 0x10> + +Optional properties: +- reg: additional physical address and length (4) of location of the + Reset Status Register (called RSTRSCR on the mpc86xx) + On the 83xx, it is located at offset 0x910 + On the 86xx, it is located at offset 0xe0094 + On the 8xx, it is located at offset 0x288 + +Example: + WDT: watchdog@0 { + compatible = "fsl,mpc823-wdt"; + reg = <0x0 0x10 0x288 0x4>; + }; -- cgit v1.2.3 From 8562205592a69dd8817f9ff361fc0ffc55f5e9fe Mon Sep 17 00:00:00 2001 From: Marek Behún Date: Mon, 24 Sep 2018 13:06:52 +0200 Subject: dt-bindings: watchdog: Document armada-37xx-wdt binding MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This adds device tree binding documentation for the CPU watchdog found on Armada 37xx SOCs (EspressoBin, Turris Mox). Signed-off-by: Marek Behún Cc: Rob Herring Cc: devicetree@vger.kernel.org Reviewed-by: Rob Herring Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- .../bindings/watchdog/armada-37xx-wdt.txt | 23 ++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 Documentation/devicetree/bindings/watchdog/armada-37xx-wdt.txt (limited to 'Documentation') diff --git a/Documentation/devicetree/bindings/watchdog/armada-37xx-wdt.txt b/Documentation/devicetree/bindings/watchdog/armada-37xx-wdt.txt new file mode 100644 index 000000000000..a8d00c31a1d8 --- /dev/null +++ b/Documentation/devicetree/bindings/watchdog/armada-37xx-wdt.txt @@ -0,0 +1,23 @@ +* Armada 37xx CPU Watchdog Timer Controller + +Required properties: +- compatible : must be "marvell,armada-3700-wdt" +- reg : base physical address of the controller and length of memory mapped + region. +- clocks : the clock feeding the watchdog timer. See clock-bindings.txt +- marvell,system-controller : reference to syscon node for the CPU Miscellaneous + Registers + +Example: + + cpu_misc: system-controller@d000 { + compatible = "marvell,armada-3700-cpu-misc", "syscon"; + reg = <0xd000 0x1000>; + }; + + wdt: watchdog@8300 { + compatible = "marvell,armada-3700-wdt"; + reg = <0x8300 0x40>; + marvell,system-controller = <&cpu_misc>; + clocks = <&xtalclk>; + }; -- cgit v1.2.3 From cd69606ad05e1d6a930e2d29ac277c00108ef908 Mon Sep 17 00:00:00 2001 From: Marek Behún Date: Mon, 24 Sep 2018 13:06:53 +0200 Subject: documentation: watchdog: add documentation for armada-37xx-wdt MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add documentation for the kernel module parameters accepted by armada-37xx-wdt. Signed-off-by: Marek Behún Reviewed-by: Guenter Roeck Signed-off-by: Guenter Roeck Signed-off-by: Wim Van Sebroeck --- Documentation/watchdog/watchdog-parameters.txt | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'Documentation') diff --git a/Documentation/watchdog/watchdog-parameters.txt b/Documentation/watchdog/watchdog-parameters.txt index 6d6200ea27b8..0b88e333f9e1 100644 --- a/Documentation/watchdog/watchdog-parameters.txt +++ b/Documentation/watchdog/watchdog-parameters.txt @@ -40,6 +40,11 @@ margin: Watchdog margin in seconds (default=60) nowayout: Disable watchdog shutdown on close (default=kernel config parameter) ------------------------------------------------- +armada_37xx_wdt: +timeout: Watchdog timeout in seconds. (default=120) +nowayout: Disable watchdog shutdown on close + (default=kernel config parameter) +------------------------------------------------- at91rm9200_wdt: wdt_time: Watchdog time in seconds. (default=5) nowayout: Watchdog cannot be stopped once started -- cgit v1.2.3